In the manufacturing flow of liquid crystal display, after the machining process for the array substrate and the color film substrate is completed, the array substrate and the color film substrate are required to be arranged oppositely to form a cell. The cell forming process comprises the following four steps: firstly, coating and curing the alignment film on the array substrate and the color film substrate; and then, rubbing the cured alignment film, that is, forming grooves with a predetermined direction on the surface of the alignment film so that liquid crystal molecules are arranged in the predetermined direction; thereafter, drop injecting the liquid crystals, coating the sealant, arranging oppositely the array substrate and the color film substrate to form a cell, and curing the sealant; finally, performing the cutting process, that is, cutting the array substrate and the color film substrate after they are arranged oppositely to form a cell, to form a single liquid crystal cell.
However, after the sealant is cured, the amount of the liquid crystals in the liquid crystal cell cannot be increased or decreased, and too many or too few liquid crystals in the liquid crystal cell may cause poor liquid crystal display effect.